select name[1,8] dbspace,
sum(chksize) - sum(nfree) Pages_used,
round ((sum(nfree)) / (sum(chksize)) * 100, 2) percent_free
from sysdbspaces d, syschunks c
where d.dbsnum = c.dbsnum
group by 1
order by 1;
the result will show you how much space you have in your dbspaces
also you can execute a onstsat -d command that will sho you the free space also.
I would think that executing a query that is strictly "select ... from ... where" would not be a problem for any user but if you cannot execute a "select ... from ... where ... into ...." statement then perhaps this is a problem with the userID and/or directory permissions if you're using cooked space.
Even though it's a temp table that your referencing (selecting into) you are still writting to the database with the intention of creating something & you may not have permission to create a table even if it is temporary.
What happens if you login as the owner of the database which is probably userID "informix"?